1. Field of the Invention
The invention relates to railway rolling stock and more particularly to house cars of the type in which the sides are wholly formed of movable doors, partly of the transversely movable and longitudinally slidable type and partly of the longitudinally slidable type and consists particularly in an improved arrangement of the doors, safety features and an improved seal for such doors.
2. The Prior Art
The prior art includes cars in which there are two sets of adjacent doors covering an elongated opening and having a pair of parallel supporting tracks on the car side sill and a pair of parallel retainer rails on the car side plate. Thomas C. Soddy U.S. Pat. No. 3,056,176, which is owned by the assignee of the present application, discloses and claims a structure of this type in which one of the doors is a simple sliding door and the other door is a plug door with mounting cranks of sufficient length to permit the plug door to be moved transversely outwardly of the sliding door and longitudinally abreast of it to clear the opening.
In cars of the all-door type, the elongated opening may be closed by four plug doors, each of which is supported from the car side by a pair of rotatable mounting shafts and associated crank arms along with mechanism for operating the shaft. This arrangement requires that all four doors be equipped with relatively complex means for shifting them transversely of the car side.
In another prior art embodiment of all-door type cars, the combination of plug and sliding doors disclosed in U.S. Pat. No. 3,056,176 is utilized, the car side being closed by one or more simple sliding doors adjacent each end of the car side and a pair of adjacent plug doors at the middle of the car side, one of the plug doors being in overlapping relation with the other plug door and both plug doors being in overlapping relation with the adjacent vertical edges of the simple sliding doors, the edges of the sliding doors remote from the plug doors being overlaid by flanges on the adjacent edges of the adjacent plug doors. In this arrangement, no means is provided for maintaining the edges of the simple sliding doors remote from the plug doors in tight engagement with the car side sill and side plate so that during movement of the car the simple sliding doors would be free to move into and out of engagement with the side sill and side plate with consequent noise, frictional wear on the sliding door rollers and track, inferior weather tightness and weakening of the car structure.
In the previous door arrangements referred to above, the top retainer rails have been at different levels and have had a single vertical flange depending from a transverse flange or web on the side plate. In cars having a full length door opening with the side plate and roof unsupported between the car ends, substantial deflection of the unsupported side plate frequently causes frictional wear between the top retainer crank rollers and the top retainer rail flange, resulting in the destruction of the rollers and the cutting through the flange and the door falling off the car, with consequent danger to personnel and railroad property.